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// isFinite()
/*
Checks whether a value is a finite number.
Finite is a number that isn't infinite and can be measured or given a value.
It only takes a single parameter which is the value you'd like to check.
It's return value will be a boolean (true or false)
Numbers that pass as finite:
0
whole numbers
negative numbers
decimals
equations
*/
console.log(Number.isFinite(80)); // output = true
console.log(Number.isFinite(-1.80)); // output = true
console.log(Number.isFinite(2 * 2)); // output = true
console.log(Number.isFinite(80)); // output = true
console.log(Number.isFinite(0)); // output = true
console.log(Number.isFinite("10/17/2019")); // output = false
console.log(Number.isFinite("3")); // output = false
// isInteger()
/*
Checks whether the value passed is an integer.
It's return value will be a boolean (true / false)
*/
console.log(Number.isInteger(2)); // output = true
console.log(Number.isInteger(-10)); // output = true
console.log(Number.isInteger(2.50)); // output = false
console.log(Number.isInteger(0)); // output = true
// isNaN()
/*
Checks whether the value passed is NaN (Not a number) or if the value is a number
true = NaN
false = A number
*/
console.log(Number.isNaN(436)); // output = false
console.log(Number.isNaN(91.9)); // output = false
console.log(Number.isNaN("76")); // output = false
console.log(Number.isNaN(true)); // output = false
console.log(Number.isNaN(NaN)); // output = true
console.log(Number.isNaN("NaN")); // output = false
// isSafeInteger()
/*
Checks whether the method passed is a safe integer. The returned value will provide a boolean.
A safe integer is represented as an IEEE-754 double precision number. This is simply any number between -9007199254740991 and 9007199254740991.
Note that the value isn't changed to a number if a string is passed in.
*/
Number.isSafeInteger(9); // true
Number.isSafeInteger(-234); // true
Number.isSafeInteger("234"); // false
Number.isSafeInteger(0.7); // true
Number.isSafeInteger(2.0); // true
// toExponential()
/*
Converts a number to its exponential form. The returned value is a string that represents the Number object in exponential notation
*/
const num1 = 89.0;
num.toExponential(); // '"8.9e+1"
const num2 = 2.5692;
num.toExponential(); // "2.5691e+0"
const num3 = -100.45;
num.toExponential(); // "-1.0045e+2"
// toFixed()
/*
Formats a number using the fixed-point notation. It allows you to format a number with a specific number of digits to the right of the decimal. Numbers will be rounded is ncessary.
Its return value is a string with the given number using fixed-point notation. If the number given is negative, the return value will be a number and won't be converted into a string.
*/
3.45.toFixed(); // '"3"
3.45.toFixed(1); // "3.5"
48573.120.toFixed(5); // "48573.12000"
3.45.toFixed() - // "3"
180.45.toFixed(); // -100
// toLocaleString()
/*
Converts a number into a language-sensitive representation of said number.
It can take in two optional parameters:
- locales: A string with a language tag (bali, latn)
- options: A set of options for the given locale (curency, style)
The return value is a string.
*/
let number = 8000;
number.toLocaleString(); // "8,000" because the locale is English
number = 800;
number.toLocaleString("ja-JP", { style: "currency", currency: "JPY" }); // "￥800" because we set the the locale and options
// toPrecision()
/*
Converts a number to the specified precision.
The returned value is in the form of a string. The value will be rounded and padded with 0's if there are not enough digits.
*/
const precisionNum = 9.473739;
console.log(precisionNum.toPrecision()); // "9.473739"
console.log(precisionNum.toPrecision(4)); // "9.474"
console.log(precisionNum.toPrecision(1)); // "9"
// toString()
/*
Converts a given number to a string with the specified base number (an integer betwen 2 and 36)
The return value is given in the form of a string if no radix is given.
*/
const toStringNum = 100;
toStringNum.toString(2); // "1100100"
toStringNum.toString(); // "100"
toStringNum.toString(4); // "1210"
// valueOf()
/*
Returns the number value in primitive form of a Number object.
This is rarely something done on your own, as JavaScript invokes this automatically.
*/
const age = new Number(45);
typeof age; // object
age.valueOf(); // 45